TypeScript call function with Rest Parameters from another with Rest Parameters

This is a bug in the compiler and is getting fixed right now [v0.8]. Lambdas currently give error messages with optional and rest parameters. Please use the long function syntax if this is a blocking issue.

Classes can't match that interface. The closest you can get, I think is this class, which will generate code that functionally matches the interface (but not according to the compiler).

class MyType implements MyInterface {
  constructor {
    return "Hello";
  }
}
alert(MyType());

This will generate working code, but the compiler will complain that MyType is not callable because it has the signature new() = 'string' (even though if you call it with new, it will return an object).

To create something that actally matches the interface without the compiler complaining, you'll have to do something like this:

var MyType = (() : MyInterface => {
  return function() { 
    return "Hello"; 
  }
})();
alert(MyType());